Preheat oven to 425 degrees F. Lightly oil a baking sheet or coat with nonstick spray.
In a small bowl, whisk together soy sauce, oyster sauce, rice wine vinegar, brown sugar, ginger, garlic, sesame oil, cornstarch and Sriracha, if using; set aside.
Place chicken, carrots and bell peppers in a single layer onto the prepared baking sheet. Stir in soy sauce mixture and gently toss to combine.
Place into oven and bake for 16-18 minutes, or until the chicken is cooked through. Stir in broccoli and snow peas during the last 7-10 minutes of cooking time.
Serve immediately, garnished with sesame seeds and green onion, if desired.
Notes
*16 ounces broccoli florets is equal to about 3 cups.